* Corresponding author: Yasin Baykalir Copyright © 2023 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. The effects of different light spectrum on some oxidative stress parameters in male and female rats Nurhan Trasci 1 , Yasin Baykalir 2, * and Ulku Gulcihan Simsek 3 1 Department of Animal Science, Experimental Animal Production Application and Research Center, Adiyaman University, Adiyaman, Turkey. 2 Department of Biostatistics, Faculty of Veterinary Medicine, Balikesir University, Balikesir, Turkey. 3 Department of Animal Science, Faculty of Veterinary Medicine, Firat University, Elazig, Turkey. GSC Biological and Pharmaceutical Sciences, 2023, 25(02), 123–128 Publication history: Received on 05 August 2023; revised on 05 November 2023; accepted on 08 November 2023 Article DOI: https://doi.org/10.30574/gscbps.2023.25.2.0383 Abstract The objective of this study was to investigate oxidative stress parameters in plasma, liver, and brain of Sprague Dawley rats grown under a compact fluorescent lamp with purple, blue, green, yellow, orange, red, and white. For this purpose, 56 male and 56 female rats were housed in standard cages under seven different light colors from weaning until puberty. Malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase (GPx) in plasma, liver, and brain were examined as oxidative stress parameters. Two factors which are gender and light were investigated regarding the main effects by Two-way ANOVA with the General Linear Model procedure. The different light spectrums had a significant impact on MDA, GSH and, GPx of plasma, liver, and brain (P<0.05). The red group resulted the highest in plasma, liver, and brain MDA. In addition, some of the examined parameters were different for the gender basis. The plasma GSH, the liver MDA, the liver and brain GPx were different in male and female rats (P<0.05). Only the liver GPx enzyme activity was higher in male rats, the other parameters in the female rats had a higher value. In conclusion, low-wavelength lights may be more useful for rats’ environments when compared to high wavelengths in manner oxidative stress. However, illumination is not the sole phenomenon for raising animals. Environmental demands may vary from time to time and even according to gender. Moreover, it may be useful for studies to be conducted by considering other lighting factors such as intensity and cycle. Keywords: Light Spectrum; Lighting; Rat; Oxidative Stress 1. Introduction Light is an important macro-environment factor for organisms. Light significantly affects organisms for the ordinary course of growth and development, muscle and bone development, immune system, hormone and enzyme systems, and daily activities. Therefore, lighting design should be optimally balanced in animal houses the maintain an optimal environment [1,2]. Light is a special form of energy that has a certain energy and frequency, moves in the form of waves, and is explained by particle effect, wave, and photon theories. It can also be defined as the propagation of very small atomic particles in the form of waves. Electromagnetic radiations of different shapes all travel in space as energy waves. The region between the two waves formed is called the wavelength. Since the wavelength ranges from 380 nm to 780 nm infinitely, there are an infinite number of colors from purple to red. The smallest wavelengths of the visible spectrum correspond to purple, and the largest wavelengths to red. Visible electromagnetic waves are visible light waves. In healthy people, the eye can perceive between 380 and 780 nm [3]. Light greatly affects the appearance, behavior, and physiology of rats. The effect of light on rats is much greater than its effects on the eyes. Light, which is the most important factor of circadian rhythm, is necessary for daily life, endocrine